In conference and meeting presentations, images are displayed on a monitor or projected on a screen for audience viewing. A speaker calls attention to specific portions of the displayed images using pointing devices such as illuminated arrows and laser pointers. Although laser pointers are generally preferred pointing devices, there are various limitations associated with the use of laser pointing devices. For example, the size of the projected image is typically large, especially in auditorium settings, and the speaker is positioned relatively close to the projected image. At this relatively close proximity to the projected image, the speaker cannot easily view the entire image, and there is significant perspective distortion when viewing projected images up close. Therefore, the speaker cannot easily view the presentation and must use a small computer screen on which the images are simultaneously displayed, alternating attention between the computer screen and the projected image.
Since laser pointers are typically held in the hand of the speaker and manually moved to the desired locations on the projected images, laser pointers are susceptible to motion jitter, causing inaccurate pointing and viewing problems for the audience. Moreover, the speaker has to face the projected image to ensure that the correct areas of the screen are selected using the laser pointer, preventing eye contact between the speaker and the audience. In addition, the use of these physical highlighting systems are only applicable to presentations given at a single location and not to presentations made simultaneously to multiple distributed locations, for example across a computer network or through a video conference.
Systems have been developed in an attempt to overcome the limitations of using physical and optical pointers in group presentations. For example, U.S. Pat. No. 6,747,636 is directed to a display system for overlaying graphics applied to a display surface onto the graphics output of an application running in the foreground, and to allow user input to the application program by means of a touch sensitive screen. In this way, a completely interactive display system is provided in which the user can highlight and edit information generated by the computer program by simply drawing on the touch sensitive screen. In operation, when a user selectively applies pressure in the form of a point, line or script to the surface of a touch screen, information is conveyed by the touch screen to a computer, which in response updates the image projected by the computer screen with the user script and reproduces such information at a sufficient rate that user drawings on the board become interactive. Alternatively, the computer can interpret the user's touch input, and in response emulate operation of the mouse, a light pen or a digital command, for conveying information to the application program being executed. User script is overlaid onto the image, causing the image to be updated to include the user drawing, for example, points, lines, or script. The system however, does not attempt to interpret the drawings made by the user or to correct errors or waviness in the points, lines or script entered by the user on the touch screen. In addition, the system does not provide for enhancing contrast between the drawings entered by the user and the information displayed by the computer on the LCD screen in order to enhance the ability of the viewing audience to identify the highlighted areas of a projected image.
U.S. Pat. No. 6,538,643 is directed to a method and system for presenting slides in which touch pad portions of a touch pad are mapped to pre-selected parts of a presented slide such that a pre-selected part of the present slide is highlighted in response to the corresponding touchpad portion being touched. Instead of highlighting portions of the slide, color change, outlining or other ways of distinguishing the selected portions of the slide can be used. An operator generates slides to be displayed on a display screen and associates highlighting techniques, such as color change, blinking or brightening, animated builds, check marks or underlining with a pre-selected part, point, portion or attribute of the slides for drawling audience attention to the pre-selected parts of the slides. The operator may then touch a touch pad portion of touch pad to execute the highlighting of a corresponding pre-selected part of the slide. This system, however, requires pre-selection of areas of a presentation slide, association of a pre-determined highlighting technique with each pre-selected area and mapping each pre-selected area to a specific portion of the touchpad device. The system does not provide for random, real-time user input of highlighting during a presentation or for the selection of random areas of the presentation slide outside of the pre-selected areas. In addition, the system does not maximize the highlighting contrast between the pre-selected areas of the presentation slide and the non-selected areas of the presentation slide.
U.S. Pat. No. 5,428,417 is directed to a visual lecture aid that provides a lecturer with a remote-controlled touch panel assembly, which makes available any one of a group of stored graphic icon pointers and highlighters that can be seen by the lecturer on a display panel. These icon pointers and highlighters include highlighting overstrikes and highlighting squares. The lecturer utilizes the remote-controlled touch panel to select each of the pointing and highlighting icons by touch selection from a menu of displayed icons on the display panel and sequentially positions each icon and overstrike highlighting line by a simple finger movement over the display panel and subsequently freezes the final position of each pointing icon by touching a displayed freeze button. In addition to the graphics, both projected color selection and brightness control are available to the lecturer from a remote controlled display panel. This system, however, only provides for the selection of specific predefined graphics and does not allow for entry or recognition of user-defined graphics or shapes on the touch screen. In addition, the color selections and brightness are predefined within the system, and the user must select from one of these predefined colors. The colors, however, are not created or selected to maximize the contrast of the display screen over which the selected graphics are displayed.
Therefore, a need exists for a pointing system that enables a speaker to maintain eye-contact with the audience, and to point at objects on the displayed screen without introducing motion jitter. Suitable systems will provide for random and real-time user selection of highlighted regions of a selected image during the course of the presentation while permitting the speaker to generally maintain focus and eye-contact with the audience. Color contrast of the highlighted area will be selected to maximize contrast with the portions of image to be highlighted. In addition, the system can work with computer generated highlights and with conventional laser pointers.